On Fr, 12.04.24 09:33, 细石泉 (nicheln...@gmail.com) wrote: > systemd will write log to console directly when bootup. A unexpected serial > console flow control maybe block systemd at embedded systems. I guess > systemd doesn't do a good job of initializing the serial console.
It doesn't do any job of it. We try hard to not reconfigure the serial port at all, and we tell getty to not do this either. The assumption is that whatever you configure on the kernel cmdline should remain in effect all the way through. > If a noise XOFF(HEX13) generate when systemd bootup, systemd stucked. > Should systemd turn off any flow control stuff when initializing the serial > console? Tell the kernel what kind of flow control you want, we should not reconfigure things then. Note that iirc XON/XOFF handling is enabled on by default on most linux ttys, i.e. "stty" will generally report "ixon" on terminals, including graphical ones. And C-S/C-Q is generally understood to just work to suspend terminal output. Hence, turning this off would probably be quite confusing to most. Lennart -- Lennart Poettering, Berlin
